No, the egg is not released in period blood.
Understanding the Menstrual Cycle
The menstrual cycle involves several phases. A mature egg is released from an ovary during ovulation, which typically occurs midway through the cycle. If the egg isn't fertilized, the uterine lining (endometrium), which has thickened to prepare for a potential pregnancy, breaks down. This breakdown of the uterine lining, along with blood and other tissue, is what constitutes menstrual bleeding, or a period. This blood is discharged through the vagina. The released egg itself does not leave the body in the menstrual blood; it disintegrates if not fertilized.
- Ovulation: The release of a mature egg from the ovary. This occurs before the menstrual bleeding begins.
- Menstruation: The shedding of the uterine lining, blood, and tissue. This occurs after ovulation, if fertilization does not occur.
- Menstrual blood: The blood and tissue expelled from the vagina during menstruation; this does not contain the egg.
As stated in one reference, "When pregnancy does not occur, the egg and lining of the uterus are shed from the vagina during a menstrual bleed." It's crucial to understand that the phrasing "the egg and lining" refers to the fact that the lining sheds, and the egg, having already been released earlier in the cycle, disintegrates if unfertilized. The egg itself is not present within the menstrual flow.
Multiple reputable sources confirm this understanding of the menstrual cycle [1, 2, 3, 4, 5, 6, 7, 8, 9, 10].
